U.S. patent application number 11/937214 was filed with the patent office on 2008-07-03 for sensor system for a refrigerator dispenser.
Invention is credited to Bob A. Ghent, Chad Lange, Peter J. Richmond.
Application Number | 20080156008 11/937214 |
Document ID | / |
Family ID | 39324036 |
Filed Date | 2008-07-03 |
United States Patent
Application |
20080156008 |
Kind Code |
A1 |
Richmond; Peter J. ; et
al. |
July 3, 2008 |
Sensor System for a Refrigerator Dispenser
Abstract
A refrigerator includes a dispenser, a dispenser well, a control
for regulating a dispensing operation, and a sensor system for
automatically initiating and terminating the dispensing operation.
The sensor system includes at least one capacitive-type sensor
mounted in the dispenser well. The sensor is configured to detect
the presence of a container in the dispenser well, an upper edge
portion of the container and a level of liquid filling the
container during the dispensing operation. The sensor signals the
control to automatically cease the dispensing operation before the
level of liquid reaches the upper edge portion of the container.
The control is configured to differentiate between animate and
inanimate objects, while preventing any release of water or ice
when an animate object is detected.
Inventors: |
Richmond; Peter J.; (Berrien
Springs, MI) ; Ghent; Bob A.; (St. Joseph, MI)
; Lange; Chad; (St. Joseph, MI) |
Correspondence
Address: |
DIEDERIKS & WHITELAW, PLC
12471 Dillingham Square, #301
Woodbridge
VA
22192
US
|
Family ID: |
39324036 |
Appl. No.: |
11/937214 |
Filed: |
November 8, 2007 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60877668 |
Dec 29, 2006 |
|
|
|
Current U.S.
Class: |
62/178 ;
222/1 |
Current CPC
Class: |
G01F 11/284 20130101;
F25D 23/126 20130101 |
Class at
Publication: |
62/178 ;
222/1 |
International
Class: |
F25D 23/12 20060101
F25D023/12; B67D 1/00 20060101 B67D001/00 |
Claims
1. A refrigerator comprising: a cabinet; at least one refrigerated
compartment arranged within the cabinet; a door mounted to the
cabinet for selectively providing access to the at least one
refrigerated compartment; and a dispenser assembly provided in the
door for selectively releasing at least one of water and ice to a
consumer, said dispenser assembly including: a main body portion; a
control portion provided on the main body portion, said control
portion including a plurality of control elements for selecting a
desired dispensing operation; a dispenser well provided in the main
body portion, said dispenser well including a base section and an
upstanding wall section; a control operatively connected to the
plurality of control elements for regulating the dispensing
operation; and a sensor system including at least one passive
sensor extending along the wall section of the dispenser well, said
at least one passive sensor being configured to detect a container
placed within the dispensing well, an upper rim portion of the
container and a level of the at least one of water and ice released
into the container during the dispensing operation, said control
automatically initiating a dispensing operation based on the
presence of the container in the dispenser well and thereafter
automatically terminating the dispensing operation before the level
of liquid reaches the upper rim portion of the container.
2. The refrigerator according to claim 1, wherein the at least one
passive sensor is constituted by a capacitive-type sensor.
3. The refrigerator according to claim 2, wherein a capacitive-type
sensor includes a plurality of capacitive plates.
4. The refrigerator according to claim 3, wherein the plurality of
capacitive plates are arranged in a substantially vertical row
extending along the wall section of the dispenser well.
5. The refrigerator according to claim 3, wherein the plurality of
capacitive plates are interconnected by a common metal strip.
6. The refrigerator according to claim 1, wherein the at least one
passive sensor is constituted by at least one capacitive strip,
said at least one capacitive strip including a plurality of
discrete sensing zones.
7. The refrigerator according to claim 6, wherein the at least one
capacitive strip extends substantially vertically along the wall
section of the dispenser well.
8. The refrigerator according to claim 7, wherein the at least one
capacitive strip is constituted by first and second capacitive
strips extending substantially vertically, at spaced locations,
along the wall section of the dispenser well.
9. A refrigerator comprising: a cabinet; at least one refrigerated
compartment arranged within the cabinet; a door mounted to the
cabinet for selectively providing access to the at least one
refrigerated compartment; and a dispenser assembly provided in the
door for selectively releasing at least one of water and ice to a
consumer, said dispenser assembly including: a main body portion; a
dispenser well provided in the main body portion, said dispenser
well including a base section and an upstanding wall section; means
for sensing a container in the dispensing well for initiating a
dispensing operation; means for passively sensing an upper edge
portion of the container placed within the dispenser well; means
for passively detecting a level of the at least one of water and
ice released into the container during the dispensing operation;
and means for automatically terminating the dispensing operation
before the level of liquid in the container reaches the upper edge
portion.
10. The refrigerator according to claim 9, further comprising:
means for differentiating between an animate object and an
inanimate object introduced into the dispenser well, said
differentiating means preventing automatic initiation of the
dispensing operation if the object introduced into the dispenser
well is an animate object.
11. The refrigerator according to claim 9, wherein the sensing
means is constituted by at least one capacitive-type sensor having
a plurality of capacitive plates.
12. The refrigerator according to claim 11, wherein the plurality
of capacitive plates are arranged in a substantially vertical row
extending along the wall section of the dispenser well.
13. The refrigerator according to claim 12, wherein the plurality
of capacitive plates are interconnected by a common metal
strip.
14. The refrigerator according to claim 11, wherein the at least
one capacitive-type sensor is constituted by at least one
capacitive strip, said at least one capacitive strip including a
plurality of discrete sensing zones.
15. The refrigerator according to claim 14, wherein the at least
one capacitive strip extends substantially vertically along the
wall section of the dispenser well.
16. The refrigerator according to claim 11, wherein the detecting
means is constituted by another capacitive strip mounted in the
dispenser well.
17. The refrigerator according to claim 16, wherein the at least
one capacitive strip and the another capacitive strip extend
substantially vertically, at spaced locations, along the wall
section of the dispenser well.
18. A method of dispensing a liquid from a refrigerator door
mounted dispenser assembly including a dispensing well comprising:
passively sensing a presence of a container in the dispensing well;
passively sensing an upper edge portion of the container;
automatically initiating a dispensing operation by introducing at
least one of water and ice into the container when the presence of
the container is sensed in the dispenser well; detecting a fill
level associated with the dispensing operation; and automatically
terminating the dispensing operation before the fill level reaches
the upper edge portion of the container.
19. The method of claim 18, wherein passively sensing a presence of
the container includes differentiating between an animate object
and an inanimate object introduced into the dispenser well, said
dispensing operation only preceding when an inanimate object is
detected.
20. The method of claim 18, wherein the passive sensing employed in
the dispensing method is performed with a pair of spaced,
substantially vertically extending capacitive sensor arrays mounted
at spaced locations within the dispenser well portion of the door.
Description
CROSS-REFERENCE TO RELATED APPLICATION
[0001] The present application claims the benefit of U.S.
Provisional Patent Application Ser. No. 60/877,668 filed Dec. 29,
2006 entitled "Sensor System for a Refrigerator Dispenser."
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] The present invention pertains to the art of refrigerators
and, more particularly, to a sensor system employed in a dispenser
mounted in a refrigerator door.
[0004] 2. Description of the Related Art
[0005] Refrigerators having built-in ice/water dispensers are well
known in the art. In general, the dispensers are mounted to a door
of the refrigerator for the purpose of dispensing ice and/or water
without requiring a user to access a refrigerator compartment. A
typical dispenser includes a dispenser well into which a container
is placed. Once the container is in position, an actuator is
operated to release the ice and/or water into the container.
[0006] In many cases, the actuator is a pressure sensitive
mechanical switch. Typically, the switch is operated by pushing the
container against, for example, a lever. The lever, in turn,
operates the switch that causes the ice and/or water to be
dispensed. A number of dispensers employ multiple actuators, one
for ice and another for water, while other dispensers employ a
single actuator. Dispensers which employ a single actuator
typically require additional control elements that enable a user to
select between ice and water dispensing operations. Several
manufacturers have converted from mechanical switches to electrical
or membrane switches. Functioning in a similar manner, a container
is pushed against the membrane switch to initiate the dispensing
operation. Still other arrangements employ actuator buttons
provided on a control panel of the dispenser. With this
arrangement, the user continuously depresses a button to release
ice and/or water into the container. In yet another arrangement,
ultrasonic sensors are mounted in the dispenser well and function
to sense a presence and size of the container. The dispenser
automatically begins dispensing ice or water based on the presence
of the container and stops dispensing before the container
overfills.
[0007] Over time, mechanical and membrane switches wear out.
Physical interaction with the switches results in wear and tear on
contact points, springs, levers and the like which eventually
require replacement. In addition, buttons, switches and sensors not
only add to the overall cost and complexity of the system, but
often poses an attraction to young children. Ever curious, young
children will often play with the dispenser controls and release
water and/or ice onto kitchen floors. In order to address this
problem, several manufactures provide their dispensers with a
"Lock-Out" feature which, when active, disables operation of the
dispenser. While effective, consumers often don't want to turn the
system on and off as needed. As such, users do not routinely avail
themselves of this option.
[0008] Another drawback with existing systems is the lack of an
automatic cut-off feature. More specifically, once activated, the
dispenser will discharge water or ice until the pressure is removed
from the actuator. If the user is momentarily distracted or if the
dispenser is operated by an inexperienced individual such as a
child, the level of ice or water can overflow the container. There
also exist drawbacks with the systems that employ automatic
actuators. Most active sensors cannot differentiate between a
container and a child's hand. Thus, in such systems, the mere act
of a child inserting a hand or other object into the dispenser well
will initiate a dispensing operation. In addition, active sensors
require both the sending and receiving of signals. Sensors of this
type may require periodic alignment and necessitate the use of
multiple components which further adds to the overall cost and
complexity of the appliance.
[0009] Therefore, despite the existence of refrigerator dispensers
in the prior art, there still exists a need for an enhanced
refrigerator dispensing system. More specifically, there exists a
need for a refrigerator dispensing system that employs passive-type
sensors, such as capacitive sensors, which do not require contact
by a container or other device to initiate a dispensing operation,
yet automatically terminate a dispensing operation when a level of
ice or water reaches an upper rim of the container. In addition,
there exists a need for a refrigerator dispensing system which
automatically differentiates between animate and inanimate objects
to prevent inadvertent dispensing operations.
SUMMARY OF THE INVENTION
[0010] The present invention is directed to a refrigerator
including a cabinet within which is defined at least one
refrigerated compartment. A door is pivotally mounted to the
cabinet to provide access to the refrigerated compartment. A
dispenser assembly is provided in the door to enable users to
obtain ice and/or water without requiring access to the
refrigerated compartment. The dispenser includes a main body
portion, a control portion including a plurality of control
elements for selecting a desired dispensing operation, a dispenser
well provided in the main body portion, and a sensor system.
[0011] In accordance with the invention, the sensor system includes
at least one passive sensor that is mounted in the dispenser well.
The sensor is configured to detect an upper edge portion of a
container placed in the dispenser well and a level of liquid
filling the container during a dispensing operation. The sensor
signals the control to automatically terminate the dispensing
operation before the level of liquid in the container reaches the
upper edge portion.
[0012] In accordance with another aspect of the invention, the
sensor system is also configured to detect when a container is
introduced into the dispenser well and automatically trigger a
dispensing operation. More specifically, upon sensing that a
container is positioned in the dispenser well, the control
automatically begins releasing water or ice into the container
based upon user preferences. In addition to sensing the presence of
a container, the control is also configured to differentiate
between animate and inanimate objects. More specifically, the
control automatically initiates a dispensing operation only upon
sensing an inanimate object, e.g. a container, in the dispenser
well. In the event that an animate object, such as a child's hand
or the like, is introduced into the dispenser well, the control
does not release the water or ice.
[0013] Additional objects, features and advantages of the present
invention will become more readily apparent from the following
detailed description of a preferred embodiment when taken in
conjunction with the drawings wherein like reference numerals refer
to corresponding parts in the several views.
BRIEF DESCRIPTION OF THE DRAWINGS
[0014] FIG. 1 is a front elevational view of a refrigerator
incorporating a dispenser having a sensor system constructed in
accordance with the present invention;
[0015] FIG. 2 is an elevational view of the sensor system of the
present invention; and
[0016] FIG. 3 is an enlarged view of the dispenser of FIG. 1
illustrating a dispensing operation in accordance with the present
invention.
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
[0017] With initial reference to FIG. 1, a refrigerator constructed
in accordance with the present invention is generally indicated at
2. Refrigerator 2 includes a cabinet 4 having a top wall 6, a
bottom 7 and opposing side walls 8 and 9. In a manner known in the
art, refrigerator 2 includes a freezer compartment 11 arranged
along side a fresh food compartment 12. Freezer compartment 11
includes a corresponding freezer compartment door 14 and fresh food
compartment 12 includes a corresponding fresh food compartment door
15. In a manner also known in the art, each door 14, 15 includes an
associated handle 17, 18. Refrigerator 2 is also shown to include a
kick plate 20 arranged at a bottom portion thereof having a vent 21
that permits air to flow into refrigeration components (not shown)
that establish and maintain desired temperatures in freezer
compartment 11 and fresh food compartment 12. In the embodiment
shown, refrigerator 2 constitutes a side-by-side model. However, it
should be understood that the present invention could also be
employed in connection with a wide variety of refrigerators,
including top mount, bottom mount, and French-style refrigerator
models.
[0018] In accordance with the invention, refrigerator 2 includes a
dispenser assembly 40 having a main housing 44 and a control panel
49. Control panel 49 includes first and second rows of control
buttons 53 and 54 which enable a user to select a preferred
dispensing operation. Control panel 49 further includes a display
57 which, in addition to functioning in cooperation with dispenser
assembly 40, enables the user to select particular operational
parameters for refrigerator 2, such as desired temperatures for
freezer compartment 11 and fresh food compartment 12. In any case,
dispenser assembly 40 includes a dispenser well 63 having a base or
container support portion 65 and a recessed, upstanding wall
section 68. A pair of passive sensors 77 and 78 that are concealed
by the upstanding wall section 68, as will be discussed more fully
below, control dispensing operations as selected by a user. More
specifically, sensors 77 and 78 operate, upon sensing a container
79 (FIG. 3), to automatically activate a valve (not shown) to
release water through a spout 80 or an auger mechanism (not shown)
to release ice cubes.
[0019] As stated above, sensors 77 and 78 are passive in nature.
That is, in contrast to active sensors, such as ultrasonic,
infrared, optical sensors or the like which require both the
transmission and receipt of signals, sensors 77 and 78 passively
sense the presence of, for example, a container in dispenser well
63. Most preferably, sensors 77 and 78 are capacitive-type sensors
which sense changes in a dielectric constant of materials brought
into proximity of back wall section 68 (sensing zones) 114 and 115.
As higher dielectric constants register larger changes in
capacitance, the present invention maximizes the detected change in
capacitance when a container is brought into proximity of back wall
section 68 (sensing zones) 114 and 115 by providing sensors 77 and
78 with corresponding common metal strips 90 and 91, as well as a
series of sensor strips 93-100 and 104-111 as best shown in FIG. 2.
Sensor strips 93-100 and 104-111, in combination with corresponding
ones of common metal strips 90 and 91, establish a plurality of
discrete sensing zones (not separately labeled) which collectively
establish respective sensing zones 114 and 115 as indicated by
dotted lines in FIG. 2 for sensors 77 and 78 respectively. By
employing multiple sensor strips, the size of each sensor 77, 78 is
minimized. This is particularly advantageous given that the smaller
the sensor, the higher the relative change when a container or
other similar inanimate object is brought into proximity. As shown
in FIG. 3, as container 79 is placed in dispenser well 63, a
control 142 monitors the capacitance of each sensor strip 93-100
and 104-111 for changes which signal the presence and/or removal of
container 79 anywhere proximate to sensing zones 114 and 115. It
should be noted that the shape, size and configuration or layout of
the sensor strip should not be limited to that illustrated in FIG.
2, as this is merley a potential embodiment.
[0020] In addition to sensing the presence of container 79, sensors
77 and 78 determine a position of container 79 in dispenser well 63
by detecting an upper rim portion 144 thereof. In contrast to the
prior art which would be capable of detecting a height of a
container relative to a bottom wall of the dispenser, the present
invention detects the actual location of upper rim portion 144 of
container 79. Thus, in the prior art, if a container where held
above the bottom wall, overfilling could still occur as the control
would register that a taller container was being used. This is not
the case with the present invention given that dispensing
terminates before the liquid reaches the upper rim as will be
detailed more fully below. In any event, when container 79 is
placed within dispenser well 63, a change in capacitance is
detected. The change in capacitance is greatest in those sensing
strips 93-100 and 104-111 directly adjacent container 79. Any one
of sensing strips 93-100 and 104-111 located above container 79
will exhibit little or no change. In this manner, control 142
monitors the capacitance in each sensor strip 93-100 and 104-111
and determines not only the presence of container 79 but also the
position of upper rim portion 144.
[0021] After detecting the presence of container 79 and the
location of upper rim portion 144, water is automatically dispensed
into container 79. As the dielectric constant of water is much
greater than most empty containers, including glass and plastic
drinking containers, the dielectric constant of the liquid will
have an additive effect on the capacitance of each sensor strip
93-100 and 104-111. Thus, as the level of water continues to rise
in container 79, the capacitance of, for example, sensor strip 106
changes proportionally with the water height. Once the water is
above the top of sensor strip 106, the capacitance associated
therewith ceases to change or, at best, will change very little. In
this manner, control 142 can readily determine the location of the
water relative to upper rim portion 144 by monitoring the change of
capacitance of each sensing strip 93-100 and 104-111. This
arrangement provides a high degree of accuracy, while still
permitting the use of a relatively minimum number of sensor strips.
Thus, in accordance with the most preferred form of the invention,
control 142 initiates a dispensing operation upon receipt of a
signal indicating the presence of container 79, and control 142
will continue the dispensing of either water from spout 80 and/or
ice through a chute (not shown) until the fill level is a
predetermined spacing, such as one inch (approximately 2.5 cm),
from upper rim 144 of container 79, at which point the dispensing
operation is automatically terminated.
[0022] In addition to the above, sensors 77 and 78 also act as a
safety feature for dispenser assembly 40. More specifically,
sensors 77 and 78 can differentiate between animate and inanimate
objects. That is, using the theory that animate objects tend to
reduce an amount of charge stored on a capacitor rather than
increase the charge, sensors 77 and 78 are able to differentiate
between a container and, for example, a hand. In the event that a
hand or other animate object is inserted into dispenser well 63,
control 142 will not initiate a dispensing operation. Thus, if a
child or inexperienced user simply inserts a hand, rather than a
container, into dispenser well 63, water will not be dispensed from
dispenser assembly 40 and fall onto a kitchen floor surface.
[0023] At this point, it should be understood that the present
invention provides for an easily manufactured and efficient passive
sensor array that automates a refrigerator dispenser assembly. The
sensor array in accordance with present invention, not only serves
to automatically initiate a dispensing operation upon sensing the
presence of a container, but detects a location of an upper rim
portion of the container and fills the container to a level below
the rim. In addition, by being able to differentiate between
animate and inanimate objects, the present invention automatically
creates a "child lock-out" feature which operates continuously
without creating an inconvenience for other users. Finally, by
employing passive sensors instead of active sensors, power
requirements for the dispensing assembly are reduced, along with
the number of components necessary to activate and control the
dispensing of water and/or ice cubes from the dispenser.
[0024] Although described with reference to a preferred embodiment
of the invention, it should be readily understood that various
changes and/or modifications can be made to the invention without
departing from the spirit thereof. For instance, while the
invention is shown with two sensor strips each having eight
sensors, various other configurations can also be employed. Also,
while described as employing capacitive-type sensors, other forms
of passive sensors could also be utilized. In general, the
invention is only intended to be limited by the scope of the
following claims.
* * * * *